Ejector control



G. L. KOTHNY EJECTOR CONTROL Filed June 50, 1925 3 Sheets-Sheet l I: I2 l3 l4 l5 ABSOLUTE PRESSURE ,INCHES MERCURY.

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w w w 1301 2mm u= mum". to WDZDDQ 8 9 ABSOLUTE PRESSURE INCHES MERCURY.

I WITNESSES ATTORNEY.

G. L. KOTHNY EJECTOR CONTROL Filed June 50, 1925 April 17, 1928.

3 Sheets-Sheet 2 INVENTOR w w v i1 ATTORNEY.

April 17, 1928. 1,666,141

L. KORTHNY EJECTOR CONTROL Filed June 50, 1925 3 Sheets-Sheet 3 .mgmumuw I "unnnnls x i f 0 INVENTOR Z; ATTORNEY.

' Patented App 17, 192 s em r s xornny',or,srnerronn, Pens-sum; AssrGNon ro'o. rr .j;wnEELER g MANUFACTURING comrAnmior .r ILansLrrr 'rENNsr vAnIA, JA ooRro tA- l 'rion or rsnNsrLvnnI'A.

" v a j nzrnoron eonrzaong A naumma .June so, 1925 sesame. 40,515.

My invention relates to a system of control for ejector apparatus utilized for raising the pressure of elastic fiuid, and more p ar' ticula-rly for producing and mainta ning 5 various degrees of vacuum in the condenser of a steam power plant, in an -evaporator,

vacuum pan, de-aerator, and, in general,

wherever sub-atmospheric pressure is to be pl'o'curecl or maintained. 1 r

7 1 "Innocordance-with my invention, in a system utilizing two or more ejectors in series or tandem, with or withoutinterstage' c0nden-sing means, there is effected" automatic control of delivery of motive fluid, as steam,

1 to one or more stages inresponse 'tochanges pindegr'eeof vacuum or absolute pressure in the condenser or other chamber to be evacuated or 'in'th'e suction chamber or chambers ofone' or'more of the ejectors of the series.

" "More particularly inaccordance with my invention, the'delivery of motive .fluid to an ejector of a series is automatically reduced or discontinued in response to rise to prede termine'd magnitude of the absolute pressure in the suction chamber of that-ejector or of an ejector in ,ejectors. i .4

r My invention'resides in an ejector control I system" of the character hereinafter degoscribed and claimed.

For an understanding of my invention'and I vfor an illustration of several of ,the1various 4 is a verticalsectional view, partly in elevation, illustrating a modified embodiment; of my invention. V 1

Fig.5 is an elevationalview ofafurthier 7 form my'invention may take.

. Fig. 6 is'a sectional'view, partly in elevation, of

is a sectionaliviem partly1n elevavalvefstructure utilizable in'my sysvutili'zalole .in mysystem. 1 Referring to F ig.'1, the curve a later .stage of the series of there is utilized tion,-qo f a modified formlof valve-structure" the operating characteristicof a two stage A represents ejector, without interstage condenser, ordinates being pounds of free air per hourcompressed by j both stages operating cumulatively, and abscissae being absolute pressures, j in'mchesofinercuryi With both stages in, operation,the total it consumption ofimotive fluid or steam Efor both stages is, for example, 500 poundsgper hour;

curve B is hour. It will be notedthat thecharacteristio curves A and 'B-inters'ect or cross each" other the operating characteristicfor the'second stage ejector opera-ting alone,} in which case the total motivefluid or steamconsumption is, for example, 375 poundsper at X,'--which*signifies that for maintaining high vacuumjas, for; example, 29 =inchesof, Y

mercury absolute, .theitwo ejectors operat lug-cumulatively are necessary, for when the second-stage? ejector operates alone, as when? no steam? or motive fluid is'Tdeliv-ered to the first stage ejector, the lowest absolute pressure isbetween 3 and 4c inches'mercuryj ab-' solute. ,Ifo procure thehigher vacuum, both ejectors operate .and consume about 500 pounds of steani'per hour.- But beyond the point X, oncurve A, that is, forfirst'stage suction pressures upwards of about 5-inches mercury absolute, the second stage ejector. operatingalone, asindicated by'curve'B, refmoves and compresses;moreairthan do'the two stages together, and more than th'is with the second stage ejector operating alone. the total'steam consumption isreduced to about 375 pounds per hour.

I A.ccordingly.;- Fig. 1illustrates-thatfor first .-stage'suction pressures, in excess 'of about 5 inches absolute, it is more; economical to shut ofi' thefirst sta e ejector'and operate the second stage ejector alone, for

not only is more air'removed and compressed, but the work is accomplished with less motive steamg" I of intersection Xlies in the. neighborhood of,

A In Fig. 2 the "curves A andiB represent the operating characteristics for both stages and for the second stage alone, 'whenutili'zing' an interstage condenser. In this case the pointi052 for example,f s'ix inches mercury. absolute,q-

V or below atmospheric pressure. '50

from which it follows that it is more economical' when the first stage suction pressure attains the order of 6 inches absolute, the

second stage shall operate alone, with less steam consumption, to remove and compress greater amounts of air.

Obviously, as the first stage suctiOnpressure rises, in the case of both Fig. 1 and Fig. 2, with both ejectors operating, the sec 0nd stage suction pressure also rlses, and therefore, for the purposes of my Invention 'her einatter described, the automatic control may be in response to either the absolute pressureobtaining in the suction chamber of thatejectoravhoso operation is to be disconti'11ued,'or. the absolute pressure obtaining in the'suction chamber of a later stage.

It will be understood that Figs. 1 and 2 are merely illuustrative, and are not limitive of my invention, which is applicable as well to ejectors having different characteristics and utilizing other quantities of motive fluid or steam.

It will further be uncerstood that my inventionis applicable to mult-i-stage ejector systems whatever may be the type or char acter of the ejectors utilized in the several stages. Referring to Fig.3, E is a first stage ejector whose suction chamber a connects with-the condenser or other chamber from 'tratedisofthe radial or disk jet type whose motive-flu]d-expanding nozzle structure is indicated at N and whose diffuser structure is indicated at D the latter discharging into the discharge passage or casing 0 having a discharge port at (Z, delivering to atmosphere, or to any suitable region at, above Motive fluid steam is delivered at any suitable pressure from any suitable source through the pipe 0 controlled by the valve 7, from which steam is delivered to the nozzle structure N of the second stage ejector E Steam is also delivered through the manually oper at-ed valve g and pipe h to the automatic valve: structure V, through which the motive steam is delivered, when the valve V is open, to the nozzle structure N of the first stage ejector E The valve structure is of any suitable character or type, responsive to changes in absolute pressure in the suctionchamber a ofthe first stage ejector, to Which chambera is made the suction pipe connection 2'. The control of the mechanism of the valve V is made such that when the absolute pressure in the chamber a-rises to a predetermined magnitude,such, for example, as corresponds with point X, Fig. 1, or about 5 inches mercury absolute, the valve V closes, thereby discontinuing delivery of motive steam to the nozzle structure 'N of to operate cumulatively, and thereby return to operatingcharacteristic A. v

Referring .to ,Fig. .4, the first stage ejector E discharges into the interstage condenser 1 in which the motive steamer condensable component of the discharge mixture is condensed, and the air and uncondensed vapors passed to thesuction chamber Z) of the second stage ejector E which in this example is a tubular ejector.

In thiscase the motive steam delivered to thenozzle structure N 01"- the first stage ejector E is again controlled by the automatic valve V, whose suction connection 2' in this example connects with the second stage suction chamber 6, whereby when the absolute pressure in the first stage suction chamber a rises to a point, as X, Fig. 2, corresponding with about 6 inches absolute pressure; the delivery of steam to the first stage nozzle structure r is discontimied; and the system iS't'lZlHS'fOli'GCl "from operating characteristic A to characteristic B, F ig. 2. r

It will be understood, however, that the connection ot the suction pipe i to the sec- 0nd stage suction chamber 7) is merely by way of example, and that in Fig. 4 the con-' nection. i may be made to the suction cham ber a, orthat inFig'. 3 the suction connection 2' may be made to the suction chamberb of the second stage ejector E? In general, however, 1t 1s preferred to make the suction connection i to the suction a lot the sta g e ejectorrsimilarly,the"

supply of steam to thenozzle structure of the second stage ejector' E is effected through the similar automatic valve V whose suction'pipe i isfconnected to the suction chamber Z) of the second stage ejectorE I Inthis system it is apparent that a. plu-' ,rality of ejectors willbe cut out of service automatically,e ther simultaneously. or in successlonein response to rise of the absolute pressures in their suction chambersto predetermined "diflerent magnitudes.

F Referring to "Fig; 6, there'is'illustrated a form of-valve mechanism utilizable' for con-' trolling the delivery of steam to the nozzle structure o fone or more stages, as described in connection with Figs. 3, sand 5. The inlet e is connected to'the *boiler or other source ofmotive fluid or steam undersuit:

ablepressure, and the port j connects with the nozzlestructure'of the ejector which is to be automatically cut into or out of serv ice. The valve member 11 is pressed towards its seat a by a spring ic, and when in the position illustrated delivery 01": steam'to the nozzle structure of the associated ejector r is discontinued A flexible or yielding diaphragm m has applied thereto the upward pull'of the spring 8; whose tension'is adjustable byth'e adjusting screw 72; and the under side of t-he' diaphragm m is subjected to the vacuum or absolute pressure obtain ing in the suction chamber of theassociated ejector, the suction pipe 2' communicating with the space beneath the diaphragm m.

The diaphragm m is attached to the pilot. 'valve 0 which,-'when the absolute pressure in the chamber below the diaphragm m rises to a predetermined 'magnitude, is raised againstits seat, thereby shutting off communication between thesteam passage p" and :the cylinderor chamber 9, in which is movto springs, allowing steam to flow from 7 able the pistonr connected to the valve-'1). In consequence, pressure upon the top of the piston 17 is discontinued and the spring 70 closes the valve 12, shutting as steam "from the nozzle structure. of the ejector. W/Vhen the absolute pressure in the suction chamber of the ejector is below a predetermined magnitude, the pilot valve 0 opens in opposition port 6, through the passage 7, pilot valve 0 to the chamber 9, causing steam'pressu're to be exerted'upon the top of the piston 7,

which then opens the valve '0 in opposition to the spring k, causing the delivery of steam to the nozzle structure of the ejector. In Fig. 7 a generally similar arrangement is shown, except in thiscase the suction pipe 71 is in part formed of a vertical column having at its bottom the U-bend t, inwhich is, disposed mercury or the like, filling the chamber beneath the diaphragm "m, which,

in this case, is normally thrust downwardjly' bythe adjustable spring "8.

when the absolute "pressure in the-suction chamber of the ejector "rises to aj-predetera P i mined magnitude, the pressure ofthe mercury o n the under side ofthe: diaphragm m increases, causing closure of i the pilot va'lvef 0 .in opposition to spring is; similarly, when the absolute pressure inthe suctionchamber I of the ejector decrea'ses below. a predeter; mined, magnitude,fthe pressure exerted by the springs uponthe diaphragm m exceeds that o-f'the mercury, the'pilot valvel opens,

causing valve 4). to open, with consequent. de-

livery of steam to the nozzle structureof the ejector. 5 It willbe understood that the valve struc tures of Figsifi and 7 .may be utilized, or that any otherQsuitable valve structure may be employed, operable, however, under the control of the. absolute pressure-in the 'suc tion chamber of an ejector. 7

It will therefore be understood that inventionis not limited to the structure or mC erof the valve structure utilized.

Itwillfurther be understood that while I have herein referred to absolute pressures 1n the SllCtlOIl chamber of an e ector, 'such reference has been utilized for brevity, for it NVlll be understood that the suction conned ,ftionwhich controls the'valve "structure may be made to any other .suitable part of the apparatusor system so long asthe valve cont'ro-l is effected in correspondence with the absolute pressure in the suction chamber "of 1'05 her-,to effect a control of the character here-- in described. i i

the ejector or any correlated pipe or cham- In the two stage ejectors her'einbetore i'e-I ferred to, when both are'op'erating, With or. without interstage condenser, it is preferred thatfthe total throat area otthe'noz'zle structure of the first stage with respect to the total throat. area of the nozzle struc ture of the second stageshallpbe such that the ratio of compression in the first stage is greater than the ratio of compression in no i raising the pressure of elastic fluidin each i of successve stages by elastic motive fluid in each'sta'ge, substantially completely discontinuing application of elastic motive fluid in an earlier ofv said stages bythe v motve fluid in response to rise to predetermined magnitude of the suctionv pressure in. said earller stage, whereby in continuing the operation a greater weight of elastic fluid iscompressed per unit of elastic motive fluid utilized. j

2. l he method/got compressing elastic plied. to the second stage.

fluid in; two stages to substantially atmospheric pressure, which comprises entraining and raising the pressure of the elastic fluid in each stage by elastic motive fluid in each stage, and completely discontinuing application of elastic motive fluid inthe first stage by utilizing the pressure of said motive fluid in response to riseof the suction pressure in said first stage to a magnitude of the order 01 five inches mercury. absolute, whereby in continuing the operation by the second stage a greater weight of elastic fluid is compressed perunit of elastic motive fluid sup- 3. The method of pheric pressure, which comprises entraining and raising the pressure of the elastic fluid in each stage by the elastic motive fluid in each stage, between stages condensing the condensable component of the discharge of the first stage, and substantially completely discontinuing application of elastic motive fluid in the first stage in response to rise of the suction pressure in said first stage to a magnitude in excess of approximately six inches mercury absolute.

i. The combination with a plurality of ejectors in staged relation, of means responsive to rise of suction pressure in a stage other than the last stage for discontinuing delivery of motive fluid to said stage, whereby upon continued operation of the other stage or stages a greater weight of elastic fluid is compressed per unit oi elastic niotive fluid supplied to the other stage or stages. V

5. The combination with two stage ejector apparatus for raising elastic fluid to substantially atmospheric pressure, of means for discontinuing delivery of motive fluid to one of said stageswhen the suction pressure of the first stage rises to the order of 3 inches mercury absolute, whereby upon continued operation of the second stage a greater weight of elastic fluid is compressed per unit of elastic motive fluid supplied to the second stage.

6. The combination with two stage ejector compressing elasticl'lLllCl in two stages to substantially atmosapparatus for raising elastic fluid to substantially atmospheric pressure, the ratio of compression of the first stage being greater than the ratio of compression of the second stage for all first stage suction pressures less than about 5 inches mercury absolute, 01 means responsive to rise of first stage suction pressure to the order of 5 inches mercury absolute for discontinuing delivery of motive fiuid to said first stage, whereby upon continued operation of the second stage greater w ight of elastic fluid is compressed per unit of elastic motor fluid supplied to the second stage. 7. The combination with two stage ejector apparatus for raising elastic fluid to. subs anti-ally atmospheric pressure, of an intersiage condenser, and means responsive to rise of first stage suction pressure to a magnitude in excess of about six inches mercury absolute for discontinuing delivery of H- tire fluid to said first stage, whereby upon continued operation of the second stage a greaterweight of elastic fluid is compressed per unit of elastic motive fluid. supplied to the second stage. '2 7 h 8. The combination with a plurality of ejectors in staged relation, of a valve through which elastic motive fluid is sup,- plied to the motive-fluid-expanding nozzle structures ot said ejectors,and a valve intervening between said valve and the nozzle structure of one of said ejectors constituting a stage preceding another of saidejectors, said second named valve responding automatically to open when the suction pressure of the ejector with which it'is associated decreases to a predetermined magnitude, whereby upon opening said first named valve motive fluid is supplied to the nozzle structure of said other of said ejectors until the suction pressure of said one of said ejectors decreases to said predetermined magnitude, whereupon said second named valve opens and motive fluid is delivered through said first and second named'valves to elleet co-operation of said ejectors.

GOTTDANK L. KOTHNY.

CERTIFICATE 0F CGRRECTWN,

.Patent NO. 1,666,141. Granted April 17, 1926, to

GOTTDANK L. KOTHNY.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 2, line 19, for the misspelled Word "illuustrative" read "illustrative", and line 74, for the word "ejectors'read "ejector"; page 3, line 117, claim 1, for the Word "comprising" read "compressing" and line 120, for the misspelled word "successve" read "successive"; page 4, claim 5, end of line 43, insert the numeral 5, and line 62, claim 6, for "motor" read "motive"; and that the said Letters Patent should be read with these corrections therein that the same may contorrn to the record of the case in the Patent Office.

Signed and sealed this 29th day of May, A. D. 1928.

M. .l Moore,

(Seal) Acting Commissioner of Patents. 

